Location awareness remains the key for many potential future applications of distributed wireless ad hoc sensor networks (WSNs). While the location of a WSN node can be estimated by incorporating Global Positioning System (GPS) devices, it is not suitable to embed GPS receivers in every node considering the cost and size of these devices as well as from an optimization point of view. However, a small number of WSNs nodes called anchor nodes are able to resolve their location either through fixed deployment or using GPS receivers, and thereby provide the reference framework for localization of other nodes. The measurement devices in individual nodes are often erroneous for tiny WSNs nodes, and hence, robustness is a major issue for localization. In this paper, a theoretical localization framework in the presence of noise is postulated, which achieves accurate positioning compared to the existing theoretical approaches. The paired measurement localization (PML) strategy is evaluated through simulations under various noise conditions and environmental modeling, and practically verified by a testbed implementation with real motes. The results corroborate the improved positioning as well as the robustness of PML for ad hoc wireless sensor networks in the presence of noise.